1. A car insurance company wants to know what proportion of drivers always wear a seatbelt. They survey a simple random sample of 400 drivers, of which 328 say that they always wear their seatbelt.

(a) [3 marks] Compute a 99% confidence interval for the population proportion of drivers who would say that they always wear a seatbelt. Show all your steps and write out the formulas that you use.

(b) [2 mark] Based on this interval estimate, can we conclude (with 99% confidence) that more than 75% of drivers would say that they always wear a seatbelt? Explain.